Document headings vary by document type but may contain
                    the following: the agency or agencies that issued and signed a document
the number of the CFR title and the number of each part
                      the document amends, proposes to amend, or is directly
                      related to
the agency docket number / agency internal file number
the RIN which identifies each regulatory action listed in
                      the Unified Agenda of Federal Regulatory and Deregulatory
                      Actions See the
                    Document Drafting Handbook
                    for more details.
 Department of Transportation Federal Aviation Administration 14 CFR Part 39
[Docket No. FAA-2023-2398; Project Identifier AD-2023-00423-T]
RIN 2120-AA64
 AGENCY: Federal Aviation Administration (FAA), DOT.
 ACTION: Notice of proposed rulemaking (NPRM).
 SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) for all The Boeing Company Model 787-8, 787-9, and 787-10 airplanes. This proposed AD was prompted by a report indicating that the oxygen supply tubing can become kinked when certain passenger service unit (PSU) oxygen panel assemblies are installed in the forward-most position of a center stow bin. This proposed AD would require a one-time inspection of the affected PSU oxygen panel assemblies and applicable on-condition actions. This proposed AD would also prohibit the installation of affected parts. The FAA is proposing this AD to address the unsafe condition on these products.
 DATES: The FAA must receive comments on this proposed AD by February 5, 2024.
 ADDRESSES: You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods: *Federal eRulemaking Portal:*
                         Go to 
                        *regulations.gov.*
                         Follow the instructions for submitting comments.
                    *Fax:*
                         202-493-2251.
                    *Mail:*
                         U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590.
                    *Hand Delivery:*
                         Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. *AD Docket:*
                         You may examine the AD docket at 
                        *regulations.gov*
                         under Docket No. FAA-2023-2398; or in person at Docket Operations between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this NPRM, any comments received, and other information. The street address for Docket Operations is listed above. *Material Incorporated by Reference:* For service information identified in this NPRM, contact Boeing Commercial Airplanes, Attention: Contractual & Data Services (C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740-5600; telephone 562-797-1717; website*myboeingfleet.com.*
                    You may view this service information at the FAA, Airworthiness Products Section, Operational Safety Branch, 2200 South 216th St., Des Moines, WA. For information on the availability of this material at the FAA, call 206-231-3195. It is also available at*regulations.gov*
                         by searching for and locating Docket No. FAA-2023-2398.
 FOR FURTHER INFORMATION CONTACT: Samuel Nalbandian, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone 206-231-3993; email: 
                        *Samuel.K.Nalbandian@faa.gov.*


SUPPLEMENTARY INFORMATION: Comments Invited The FAA invites you to send any written relevant data, views, or arguments about this proposal. Send your comments to an address listed under 
                    **ADDRESSES**
                    . Include “Docket No. FAA-2023-2398; Project Identifier AD-2023-00423-T” at the beginning of your comments. The most helpful comments reference a specific portion of the proposal, explain the reason for any recommended change, and include supporting data. The FAA will consider all comments received by the closing date and may amend this proposal because of those comments. Except for Confidential Business Information (CBI) as described in the following paragraph, and other information as described in 14 CFR 11.35, the FAA will post all comments received, without change, to regulations.gov, including any personal information you provide. The agency will also post a report summarizing each substantive verbal contact received about this NPRM. Confidential Business Information CBI is commercial or financial information that is both customarily and actually treated as private by its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public disclosure. If your comments responsive to this NPRM contain commercial or financial information that is customarily treated as private, that you actually treat as private, and that is relevant or responsive to this NPRM, it is important that you clearly designate the submitted comments as CBI. Please mark each page of your submission containing CBI as “PROPIN.” The FAA will treat such marked submissions as confidential under the FOIA, and they will not be placed in the public docket of this NPRM. Submissions containing CBI should be sent to Samuel Nalbandian, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 206-231-3993; email: 
                    *Samuel.K.Nalbandian@faa.gov.*
                     Any commentary that the FAA receives that is not specifically designated as CBI will be placed in the public docket for this rulemaking. Background The FAA has received a report indicating that a pinching condition may exist between the oxygen supply tube on the PSU oxygen panel and the stowage bin end blade on affected PSU oxygen panel assemblies and may result in the inability of the oxygen system to provide oxygen to the airplane's passengers in a cabin depressurization event. The PSU reverse bottle oxygen panel assembly drawing restructure introduced a conflict between lower- and upper-level assembly drawings. After the drawing restructure, the upper-level assembly drawings had corrected routing design intent, but the lower-level assembly drawings had incorrect routing definition. Installation of a PSU reverse bottle oxygen panel assembly with incorrect routing can lead to a condition where the oxygen supply tubing becomes kinked in the forward-most position of a center stowage bin. Incorrect routing of the tubing, if not addressed, could result in kinked tubing and consequent passengers' injury because of a lack of supplemental oxygen during a cabin depressurization event. FAA's Determination The FAA is issuing this NPRM after determining that the unsafe condition described previously is likely to exist or develop on other products of the same type design. Related Service Information Under 1 CFR Part 51 The FAA reviewed Boeing Alert Requirements Bulletins B787-81205-SB250277-00 RB and B787-81205-SB250278-00 RB, both Issue 001, both dated February 15, 2023. This service information specifies procedures for verifying the identification label of the 
                    ( print page 88545)
                    oxygen panel assembly, doing a general visual inspection of the oxygen supply tube and initiator cable assembly for correct installation, and doing a general visual inspection for damage of the oxygen supply tubing. The service information also specifies procedures for on-condition actions: replacing the oxygen supply tubing, re-routing of the oxygen supply tubing and initiator cable assembly, and re-identifying equipment. These documents are distinct since they apply to different airplanes. This service information is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in 
                    **ADDRESSES.** Proposed AD Requirements in This NPRM This proposed AD would require accomplishing the actions specified in the service information already described, except as discussed under “Difference Between this Proposed AD and the Service Information,” and except for any differences identified as exceptions in the regulatory text of this proposed AD. This proposed AD would also prohibit the installation of affected parts. For information on the procedures and compliance times, see this service information at 
                    *regulations.gov*
                     by searching for and locating Docket No. FAA-2023-2398. Difference Between This Proposed AD and the Service Information The effectivity of Boeing Alert Requirements Bulletins B787-81205-SB250277-00 RB and B787-81205-SB250278-00 RB, both Issue 001, both dated February 15, 2023, is limited to Model 787-8, 787-9, and 787-10 airplanes having certain line numbers. However, the applicability of this proposed AD includes all Model 787-8, 787-9, and 787-10 airplanes. Because the affected PSU oxygen panel assemblies are rotatable parts, the FAA has determined that these parts could later be installed on airplanes that were initially delivered with acceptable parts, thereby subjecting those airplanes to the unsafe condition. Therefore, Model 787-8, -9, and -10 airplanes not listed in the service information would be subject only to the parts installation prohibition of this proposed AD. Costs of Compliance The FAA estimates that this AD, if adopted as proposed, would affect 19 airplanes of U.S. registry. The FAA estimates the following costs to comply with this proposed AD: Estimated Costs
Action
Labor cost
Parts cost
Cost per product
Cost on U.S.
                             operatorsInspections and rerouting
Up to 25 work-hours × $85 per hour = Up to $2,125
$0
Up to $2,125
Up to $40,375.
 The FAA estimates the following costs to do any necessary on-condition actions that would be required based on the results of the proposed inspection. The agency has no way of determining the number of aircraft that might need the on-condition actions: On-Condition Costs
Action
Labor cost
Parts cost
Cost per
                             productReplacement of oxygen supply tube
Up to 9 work-hours × $85 per hour = Up to $765
$30
$795
 The FAA has included all known costs in its cost estimate. According to the manufacturer, however, some or all the costs of this proposed AD may be covered under warranty, thereby reducing the cost impact on affected operators. Authority for This Rulemaking Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, section 106, describes the authority of the FAA Administrator. Subtitle VII: Aviation Programs, describes in more detail the scope of the Agency's authority. The FAA is issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, section 44701: General requirements. Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action. Regulatory Findings The FAA determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD would not have a substantial direct effect on the States, on the relationship between the national Government and the States, or on the distribution of power and responsibilities among the various levels of government. For the reasons discussed above, I certify this proposed regulation: (1) Is not a “significant regulatory action” under Executive Order 12866, (2) Would not affect intrastate aviation in Alaska, and (3) Would not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. List of Subjects in 14 CFR Part 39 Air transportation
Aircraft
Aviation safety
Incorporation by reference
Safety
 The Proposed Amendment Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 14 CFR part 39 as follows: PART 39—AIRWORTHINESS DIRECTIVES
 1.The authority citation for part 39 continues to read as follows: Authority:
                    49 U.S.C. 106(g), 40113, 44701. § 39.13
 2.The FAA amends § 39.13 by adding the following new airworthiness directive: **The Boeing Company:**
                         Docket No. FAA-2023-2398; Project Identifier AD-2023-00423-T. (a) Comments Due Date The FAA must receive comments on this airworthiness directive (AD) by February 5, 2024. (b) Affected ADs None. (c) Applicability This AD applies to all The Boeing Company Model 787-8, 787-9, and 787-10 airplanes, certificated in any category. (d) Subject Air Transport Association (ATA) of America Code 35, Oxygen. (e) Unsafe Condition This AD was prompted by a report indicating that the oxygen supply tubing can become kinked when certain passenger service unit (PSU) oxygen panel assemblies are installed in the forward-most position of a center stow bin. The FAA is issuing this AD to address incorrect installation of the oxygen supply tubing in the PSU oxygen panel assemblies. The unsafe condition, if not addressed, could result in kinked tubing and consequent injury of the airplane's passengers because of a lack of supplemental oxygen during a cabin depressurization event. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Inspection of the Affected Parts For airplanes identified in Boeing Alert Requirements Bulletins B787-81205-SB250277-00 RB, Issue 001, dated February 15, 2023, and B787-81205-SB250278-00 RB, Issue 001, dated February 15, 2023: Except as specified by paragraph (h) of this AD: At the applicable times specified in the “Compliance” paragraph of Boeing Alert Requirements Bulletins B787-81205-SB250277-00 RB, Issue 001, dated February 15, 2023, or B787-81205-SB250278-00 RB, Issue 001, dated February 15, 2023, as applicable, do all applicable actions identified in, and in accordance with, the Accomplishment Instructions of Boeing Alert Requirements Bulletin B787-81205-SB250277-00 RB, Issue 001, dated February 15, 2023, or B787-81205-SB250278-00 RB, Issue 001, dated February 15, 2023, as applicable. (h) Exceptions to Service Information Specifications (1) Where the Compliance Time columns of the tables in the “Compliance” paragraph of Boeing Alert Requirements Bulletin B787-81205-SB250277-00 RB, Issue 001, dated February 15, 2023, use the phrase “the Issue 001 date of the Requirements Bulletin B787-81205-SB250277-00 RB,” this AD requires using “the effective date of this AD.” (2) Where the Compliance Time columns of the tables in the “Compliance” paragraph of Boeing Alert Requirements Bulletin B787-81205-SB250278-00 RB, Issue 001, dated February 15, 2023, use the phrase “the Issue 001 date of the Requirements Bulletin B787-81205-SB250278-00 RB” this AD requires using “the effective date of this AD.” (3) Where Boeing Alert Requirements Bulletin B787-81205-SB250277-00 RB, Issue 001, dated February 15, 2023, and Boeing Alert Requirements Bulletin B787-81205-SB250278-00 RB, Issue 001, dated February 15, 2023, specify that the corrective actions for Conditions 2, 2.2, 2.2.2, and 3 must be done before further flight, this AD requires that the corrective actions for those conditions must be done within 24 months after the effective date of this AD. (i) Parts Installation Prohibition As of the effective date of this AD, no person may install, on any airplane, a PSU oxygen panel assembly part number 4572105-XXX-0D0, or 4572175-XXX-0D0, or 4572185-XXX-0D0, where the “XXX” in the affected PSU oxygen panel assembly part numbers is any combination of numerals, that was manufactured in May 2020 or before, and does not have a supplier service bulletin modification label marked with an applicable supplier service bulletin number and date. (j) Alternative Methods of Compliance (AMOCs) (1) The Manager, AIR-520, Continued Operational Safety Branch, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or responsible Flight Standards Office, as appropriate. If sending information directly to the manager of the certification office, send it to the attention of the person identified in paragraph (k) of this AD. Information may be emailed to: 
                        *9-ANM-Seattle-ACO-AMOC-Requests@faa.gov.* (2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the responsible Flight Standards Office. (3) An AMOC that provides an acceptable level of safety may be used for any repair, modification, or alteration required by this AD if it is approved by The Boeing Company Organization Designation Authorization (ODA) that has been authorized by the Manager, AIR-520, Continued Operational Safety Branch, FAA, to make those findings. To be approved, the repair method, modification deviation, or alteration deviation must meet the certification basis of the airplane, and the approval must specifically refer to this AD. (k) Related Information For more information about this AD, contact Samuel Nalbandian, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 206-231-3993; email: 
                        *Samuel.K.Nalbandian@faa.gov.* (l) Material Incorporated by Reference (1) The Director of the Federal Register approved the incorporation by reference (IBR) of the service information listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51. (2) You must use this service information as applicable to do the actions required by this AD, unless the AD specifies otherwise. (i) Boeing Alert Requirements Bulletin B787-81205-SB250277-00 RB, Issue 001, dated February 15, 2023. (ii) Boeing Alert Requirements Bulletin B787-81205-SB250278-00 RB, Issue 001, dated February 15, 2023. (3) For service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Contractual & Data Services (C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740-5600; telephone 562-797-1717; website 
                        *myboeingfleet.com.* (4) You may view this service information at the FAA, Airworthiness Products Section, Operational Safety Branch, 2200 South 216th St., Des Moines, WA. For information on the availability of this material at the FAA, call 206-231-3195. (5) You may view this material at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, visit 
                        *www.archives.gov/federal-register/cfr/ibr-locationsoremailfr.inspection@nara.gov.* Issued on December 18, 2023. Victor Wicklund, Deputy Director, Compliance & Airworthiness Division, Aircraft Certification Service.


[FR Doc. 2023-28153 Filed 12-21-23; 8:45 am] BILLING CODE 4910-13-P